AT25M01使用说明SPIEEPROMSTM32

1、贞眉内容1.芯片访问规那么符合 AT25 系列原那么，可以找相关的例子，但是 25M01 目前没有2.芯片工作原那么，不考虑写保护问题，所有操作的第一步都是要发送写允许指令，然后重新片选有 效，发送下一步的命令。注意问题：SPI 的 EEPROM勺数据输出的原理是，在输入一个字节的同时输出一个字节，没有输入字节，就输出，所以，所谓的读数据，其实质是先发送一个数据，然后在接收一个数据。操作如下：(1) 存放器读1)先片选，在发送写允许指令，片选无效2)片选，发送读存放器指令，读存放器，片选无效(2)存放器写1)先片选，在发送写允许指令，片选无效2)片选，发送写存放器指令，写数据，片选无效(3)

2、写数据1)先片选，在发送写允许指令，片选无效2)片选，发送写数据指令，写数据，片选无效(4) 读数据1)先片选，在发送写允许指令，片选无效2)片选，发送读数据指令，读数据，片选无效注意：STM32 的 SPI 需要，每次都开启voidSPI_EEPROM_Init(void)I SPI_InitTypeDefSPI_InitStructure;GPIO_InitTypeDefGPIO_InitStructure;/*EnableSPI1andGPIOclocks*/*!SPI_FLASH_SPI_CS_GPIO,SPI_FLASH_SPI_MOSI_GPIO,SPI_FLASH_SPI_MIS

3、O_GPIO,SPI_FLASH_SPI_DETECT_GPIOandSPI_FLASH_SPI_SCK_GPIOPeriphclockenable*/RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOC|RCC_APB2Periph_AFIO,ENABLE);/*!SPI_FLASH_SPIPeriphclockenable*/RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1,ENABLE);/*!ConfigureSPI_FLASH_SPIpins:SCK*/GPIO_InitS

4、tructure.GPIO_Pin=GPIO_Pin_5;GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;GPIO_Init(GPIOA,&GPIO_InitStructure);/*!ConfigureSPI_FLASH_SPIpins:MOSI*/GPIO_InitStructure.GPIO_Pin=GPIO_Pin_7;GPIO_Init(GPIOA,&GPIO_InitStructure);/*!ConfigureSPI_FLASH_

5、SPIpins:MISO*/GPIO_InitStructure.GPIO_Pin=GPIO_Pin_6;/GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IN_FLOATING;GPIO_Init(GPIOA,&GPIO_InitStructure);/选通采用软件模式-贞眉内容/*!=(uint32_t)(1024*128*2)return0;if(addr=(uint32_t)(1024*128)addr=addr-(uint32_t)(1024*128);nss=2; elsenss=1;SPI_Cmd(SPI1,ENABLE);AT25_Wait

6、Ready(nss);SPI_WREN(nss);NSS_CS_ENABLE(nss);SPI_WriteByte(READ);SPI_WriteByte(uint8_t)(addr&0 x010000)16);/*A16*/SPI_WriteByte(uint8_t)(addr&0 x00FF00)8);/*A15-A8*/SPI_WriteByte(uint8_t)(addr&0 x0000FF);/*A7-A0*/tmp=SPI_ReadByte();NSS_CS_DISABLE();SPI_Cmd(SPI1,DISABLE);returntmp;voidAT25

7、_WriteByte(uint8_tdata,uint32_taddr)一一一精心整理精心整理贞眉内容uint8_tnss=1; uint32_ttt=1024*128*2; if(addr=tt) return;if(addr=(uint32_t)(1024*128)addr=addr-(uint32_t)(1024*128);nss=2;elsenss=1;SPI_Cmd(SPI1,ENABLE);AT25_WaitReady(nss);SPI_WREN(nss);NSS_CS_ENABLE(nss);SPI_WriteByte(WRITE);SPI_WriteByte(uint8_t)(

8、addr&0 x010000)16);/*A16*/SPI_WriteByte(uint8_t)(addr&0 x00FF00)8);/*A15-A8*/SPI_WriteByte(uint8_t)(addr&0 x0000FF);/*A7-A0*/SPI_WriteByte(data);NSS_CS_DISABLE();SPI_Cmd(SPI1,DISABLE);/多字节操作/*brief将缓冲区中的数据写到 I2CEEPRO*paramargpBuffer:缓冲区指针argWriteAddr:写地址*argNumByteToWrite:写的字节数 *retval 无

9、*/voidSPI_EE_BufferWrite(u8*pBuffer,u32WriteAddr,u16NumByteToWrite,uint8_tNSS)一一一u32NumOfPage=0,NumOfSingle=0,Addr=0,count=0;Addr=WriteAddr%I2C_PageSize;count=I2C_PageSize-Addr;NumOfPage=NumByteToWrite/I2C_PageSize;NumOfSingle=NumByteToWrite%I2C_PageSize;/*IfWriteAddrisI2C_PageSizealigned*/if(Addr=0

10、)/*IfNumByteToWriteI2C_PageSize*/else贞眉内容while(NumOfPage-)(SPI_EE_PageWrite(pBuffer,WriteAddr,I2C_PageSize,NSS);精心整理WriteAddr+=I2C_PageSize;pBuffer+=I2C_PageSize; _ if(NumOfSingle!=0)(SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS);一 一/*IfWriteAddrisnotI2C_PageSizealigned*/else(/*IfNumByteToWrit

11、eI2C_PageSize*/else NumByteToWrite-=count;NumOfPage=NumByteToWrite/I2C_PageSize;NumOfSingle=NumByteToWrite%I2C_PageSize;if(count!=0) SPI_EE_PageWrite(pBuffer,WriteAddr,count,NSS);WriteAddr+=count;pBuffer+=count; while(NumOfPage-) SPI_EE_PageWrite(pBuffer,WriteAddr,I2C_PageSize,NSS);WriteAddr+=I2C_Pa

12、geSize; pBuffer+=I2C_PageSize; _ if(NumOfSingle!=0) SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS); /*贞眉内容*brief在 EEPROM 勺一个写循环中可以写多个字节，但一次写入的字节数*不能超过 EEPROMK 的大小，AT24C0 狗贞有 8个字节*paramargpBuffer:缓冲区指针* argWriteAddr:写地址*argNumByteToWrite:写的字节数*retval 无*/voidSPI_EE_PageWrite(u8*pBuffer,u32WriteAd

13、dr,u16NumByteToWrite,uint8_tNSS)一一一SPI_Cmd(SPI1,ENABLE);AT25_WaitReady(NSS); SPI_WREN(NSS);NSS_CS_ENABLE(NSS); SPI_WriteByte(WRITE);SPI_WriteByte(uint8_t)(WriteAddr&0 x010000)16);/*A16*/SPI_WriteByte(uint8_t)(WriteAddr&0 x00FF00)8);/*A15-A8*/SPI_WriteByte(uint8_t)(WriteAddr&0 x0000FF);/*

14、A7-A0*/*Whilethereisdatatobewritten*/while(NumByteToWrite-)/*Sendthecurrentbyte*/ SPI_WriteByte(*pBuffer);/*Pointtothenextbytetobewritten*/ pBuffer+;/*SendSTOPcondition*/NSS_CS_DISABLE();SPI_Cmd(SPI1,DISABLE); /*brief从 EEPROMU面读取一块数据 *paramargpBuffer:存放从 EEPROM 卖取的数据的缓冲区指针*argWriteAddr:接收数据的 EEPROM勺

15、地址*argNumByteToWrite:要从 EEPROMgt 取的字节数 *retval 无*/voidSPI_EE_BufferRead(u8*pBuffer,u32ReadAddr,u16NumByteToRead,uint8_tNSS)一一一uint8_tnss=NSS;SPI_Cmd(SPI1,ENABLE); AT25_WaitReady(nss); SPI_WREN(NSS);NSS_CS_ENABLE(nss); SPI_WriteByte(READ);精心整理贞眉内容SPI_WriteByte(uint8_t)(ReadAddr&0 x010000)16);/*A1

16、6*/SPI_WriteByte(uint8_t)(ReadAddr&0 x00FF00)8);/*A15-A8*/SPI_WriteByte(uint8_t)(ReadAddr&0 x0000FF);/*A7-A0*/ /*Whilethereisdatatoberead*/while(NumByteToRead)*pBuffer=SPI_ReadByte();pBuffer+;NumByteToRead-;/*EnableAcknowledgementtobereadyforanotherreception*/ NSS_CS_DISABLE();SPI_Cmd(SPI1,D

17、ISABLE);/*wdz*/voidSPI_EE_BufferWrite2(u8*pBuffer,u32WriteAddr,u16NumByteToWrite)u32temp=WriteAddr+NumByteToWrite-1;u32number=WriteAddr+NumByteToWrite-1024*128; if(temp1024*128)SPI_EE_BufferWrite(pBuffer,WriteAddr,NumByteToWrite,1);一 一elseif(WriteAddr=1024*128)SPI_EE_BufferWrite(pBuffer,WriteAddr,Nu

18、mByteToWrite-number,1);SPI_EE_BufferWrite(pBuffer+NumByteToWrite-number,0,number,2);elseif(WriteAddr=1024*128) SPI_EE_BufferWrite(pBuffer,WriteAddr-1024*128,NumByteToWrite,2);voidSPI_EE_BufferRead2(u8*pBuffer,u32ReadAddr,u16NumByteToRead)I ru32temp=ReadAddr+NumByteToRead-1;u32number=ReadAddr+NumByteToRead-1024*128; if(temp1024*